1) Consider that, in the hypothetical study given in the table below, cases underestimated their exposure and, as a result, 20% of exposed cases were falsely classified as unexposed, however that the classification of controls was not affected.

True results of the hypothetical case-control study with no measurement error.

Explain whether this kind of the misclassification is random or systematic? Specify is it differential or non-differential?

b) Specify the effect it would have on the results of study?